Influence of ambient weather on the incidence of hairy caterpillars infesting sole sunflower and sunflower intercropped with pigeonpea

Abstract

Investigations were carried out during Kharif 2017 at the Research Farm of Department of Agricultural Entomology, College of Agriculture, Latur (VNKMV, Parbhani) on influence of ambient weather on seasonal incidence of Euproctis sp. and Spilosoma obliqua (Walker) infesting sole sunflower and sunflower intercropped with pigeonpea. During the investigation, Euproctis sp. and S. obliqua were emerged as major hairy caterpillars on sole sunflower and sunflower intercropped with pigeonpea. The peak population of Euproctis sp. was noticed to the extent of 1.8 and 3.2 larvae per quadrat during 40th and 39th SMW and the peak population of S. obliqua was registered to the tune of 1.4 and 2.8 larvae per quadrat during 39th and 39th SMW on sole sunflower and sunflower intercropped with pigeonpea, respectively. The larval population of Euproctis sp. infesting sole sunflower exhibited positive correlation with rainy days and minimum temperature while, negative correlation with before noon relative humidity. However, the larval population of Euproctis sp. infesting sunflower intercropped with pigeonpea exhibited positive correlation with relative humidity while, negative correlation with maximum temperature. None of the factor exhibited significantly direct positive effect on the larval population of S. obliqua infesting sole sunflower while, rainfall showed negative correlation with larval population. However, the larval population of S. obliqua exhibited direct positive correlation with after noon relative humidity while, rainfall and maximum temperature showed negative correlation with larval population of S. oblique when sunflower intercropped with pigeonpea.